International Radio's Key Pulser is designed to key a transmitter at a predetermined duty cycle to allow tuning at a safe average power level. The heat generated in a radio (or radio plus amplifier) is determined by the average power being dissipated. This can be very high if tuning is done with the key down full time. By pulsing the key line the average power can be reduced by the duty cycle of the keyed waveform.

Our Key Pulser has a digital circuit, which provides an accurately controlled duty cycle that is adjustable from 20% to 100% in steps of 10%. The pulse repetition rate is approximately 50 milliseconds. This is like a train of dots at about 48 WPM.